TY - JOUR
T1 - Cord factor and peptidoglycan recapitulate the Th17-promoting adjuvant activity of mycobacteria through mincle/CARD9 signaling and the inflammasome
AU - Shenderov, Kevin
AU - Barber, Daniel L.
AU - Mayer-Barber, Katrin D.
AU - Gurcha, Sudagar S.
AU - Jankovic, Dragana
AU - Feng, Carl G.
AU - Oland, Sandy
AU - Hieny, Sara
AU - Caspar, Pat
AU - Yamasaki, Sho
AU - Lin, Xin
AU - Ting, Jenny P.Y.
AU - Trinchieri, Giorgio
AU - Besra, Gurdyal S.
AU - Cerundolo, Vincenzo
AU - Sher, Alan
PY - 2013/6/1
Y1 - 2013/6/1
N2 - Although adjuvants are critical vaccine components, their modes of action are poorly understood. In this study, we investigated the mechanisms by which the heat-killed mycobacteria in CFA promote Th17 CD4+ T cell responses.We found that IL-17 secretion by CD4+ T cells following CFA immunization requires MyD88 and IL-1β/IL-1R signaling. Through measurement of Ag-specific responses after adoptive transfer of OTII cells, we confirmed that MyD88-dependent signaling controls Th17 differentiation rather than simply production of IL-17. Additional experiments showed that CFA-induced Th17 differentiation involves IL-1β processing by the inflammasome, as mice lacking caspase-1, ASC, or NLRP3 exhibit partially defective responses after immunization. Biochemical fractionation studies further revealed that peptidoglycan is the major component of heat-killed mycobacteria responsible for inflammasome activation. By assaying Il1b transcripts in the injection site skin of CFA-immunized mice, we found that signaling through the adaptor molecule caspase activation and recruitment domain 9 (CARD9) plays a major role in triggering pro-IL-1β expression. Moreover, we demonstrated that recognition of the mycobacterial glycolipid trehalose dimycolate (cord factor) by the C-type lectin receptor mincle partially explains this CARD9 requirement. Importantly, purified peptidoglycan and cord factor administered in mineral oil synergized to recapitulate the Th17-promoting activity of CFA, and, as expected, this response was diminished in caspase-1- and CARD9-deficient mice. Taken together, these findings suggest a general strategy for the rational design of Th17-skewing adjuvants by combining agonists of the CARD9 pathway with inflammasome activators.
AB - Although adjuvants are critical vaccine components, their modes of action are poorly understood. In this study, we investigated the mechanisms by which the heat-killed mycobacteria in CFA promote Th17 CD4+ T cell responses.We found that IL-17 secretion by CD4+ T cells following CFA immunization requires MyD88 and IL-1β/IL-1R signaling. Through measurement of Ag-specific responses after adoptive transfer of OTII cells, we confirmed that MyD88-dependent signaling controls Th17 differentiation rather than simply production of IL-17. Additional experiments showed that CFA-induced Th17 differentiation involves IL-1β processing by the inflammasome, as mice lacking caspase-1, ASC, or NLRP3 exhibit partially defective responses after immunization. Biochemical fractionation studies further revealed that peptidoglycan is the major component of heat-killed mycobacteria responsible for inflammasome activation. By assaying Il1b transcripts in the injection site skin of CFA-immunized mice, we found that signaling through the adaptor molecule caspase activation and recruitment domain 9 (CARD9) plays a major role in triggering pro-IL-1β expression. Moreover, we demonstrated that recognition of the mycobacterial glycolipid trehalose dimycolate (cord factor) by the C-type lectin receptor mincle partially explains this CARD9 requirement. Importantly, purified peptidoglycan and cord factor administered in mineral oil synergized to recapitulate the Th17-promoting activity of CFA, and, as expected, this response was diminished in caspase-1- and CARD9-deficient mice. Taken together, these findings suggest a general strategy for the rational design of Th17-skewing adjuvants by combining agonists of the CARD9 pathway with inflammasome activators.
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U2 - 10.4049/jimmunol.1203343
DO - 10.4049/jimmunol.1203343
M3 - Article
C2 - 23630357
AN - SCOPUS:84878022309
SN - 0022-1767
VL - 190
SP - 5722
EP - 5730
JO - Journal of Immunology
JF - Journal of Immunology
IS - 11
ER -